Prehistoric Puppers

SCIENTISTS have uncovered new information on the hunting methods of prehistoric dogs 40 millions year ago by analysing the skulls of lions, wolves and hyenas.

Experts in Scotland and Austria suggest that the first species of dogs, known as Hesperocyon Gregarius, pounced on its preys the same way as modern foxes and coyotes.

The findings also imply that the largest dog species to ever live, known as the Epicyon Haydeni, also hunted in a similar way.

The animal, which lived 16 million years ago, could grow to the size of a grizzly bear.

The study focused on the hunting methods of a prehistoric group of mammals known as carnivorans, which includes modern-day foxes, wolves, cougars and leopards.

Scientists at the universities of Edinburgh and Vienna used computerised scans of fossils and modern animals to create 3D models of the inner ears of 36 types of carnivorans, including six extinct species.

The study is based on research carried out by an Edinburgh PhD student Julia Schwab during her studies in Vienna. Ms Schwab, of the University of Edinburgh’s School of GeoSciences, said:

“Prehistoric dogs and modern ones generally show similarities in their hunting behaviour. But as there are just bones preserved of those ancient carnivorans we looked at the inner ear as the organ of balance. By comparing it with modern animals, it allows us to get an insight into the lifestyle and hunting behaviour of those ancient carnivorans. Like the first dog Hesperocyon gregarius had a pounce hunting behaviour like foxes do it today. And Epicyon, the biggest dog ever lived probably hunted in a similar way. However, Aelurodon a dog that lived about 16 Million years ago in North America had a similar hunting behaviour to wolfs today, who socially hunt in groups together.

“The first dogs that lived 40 Million years ago had a slim body and they wereable to climb on trees which we don’t know from any dog today. But as the environment changed to more open habitats, the dogs needed to adapt and they became bigger. Generally, there was a bigger variety of prehistoric dogs than there is today.“A next step would be to also look at the inner ear of bears and seals to see how their inner ear looks like.”

Experts found out that the size of three bony canals in the inner ear, the organ that controls balance and hearing, changed over millions of years as animals adopted different hunting styles.

Faster predators such as cheetahs, lions and wolves developed larger canal ear canals that enabled them to keep their head and vision stable while chasing their preys at full speed.

According to the research, the inner ear structure indicates whether a species descended from dog-like animals or cat-like animals.

This information helps understanding the evolution and adaptation of an extinct carnivoran mammals.

The team found that two parts of the inner ear is much larger in dog-like carnivorans.

These results provide an idea of the predatory habits and the common ancestors between prehistoric and modern carnivorans.

The study has been published in the journal Scientific Report. You can view it by clicking on this link.

You can also watch this video made by WizScience.com to know more about the Hesperocyon.